Real Estate Index Portfolio Expense Example - Portfolio [Member] - Real Estate Index Portfolio - Real Estate Index Portfolio	Dec. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 27
Expense Example, with Redemption, 3 Years	84
Expense Example, with Redemption, 5 Years	146
Expense Example, with Redemption, 10 Years	$ 331

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